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Snowmobile Arctic Cat (2004 year). Manual - part 47

4-23

ADJUSTING PILOT AIR SCREW(S)

1. While counting the rotations, carefully rotate each

pilot air screw clockwise until lightly seated.

AH006

2. Rotate each pilot air screw counterclockwise the

same number of turns as noted in step 1 for an
initial setting.

3. Synchronize the oil-injection pump (see Related

Items in this section).

ADJUSTING ENGINE IDLE SPEED

1. With the snowmobile on a shielded safety stand,

start the engine, release the brake lever lock, and
thoroughly warm up. Fine-tune each idle speed
screw and each pilot air screw until the engine
idles smoothly at the desired RPM (1500 RPM is
recommended).

NOTE: Make engine idle adjustment only after

the engine has reached running temperature.
Since the idle speed screw(s) have not been
adjusted, apply slight throttle pressure to keep the
engine running. Allow engine to warm up for 2-3
minutes.

2. On twin carburetor models after the engine has

been allowed to warm up for 2-3 minutes, adjust
engine idle by first rotating the PTO-side
carburetor idle speed screw clockwise until the
tachometer reads 1480 RPM.

3. On twin carburetor models, rotate the MAG-side

carburetor idle speed screw clockwise until
tachometer reads 1500 RPM.

AH055

4. On twin carburetor models, rotate the PTO-side

carburetor idle speed screw clockwise until the
tachometer reads slightly above 1500 RPM; then
rotate the idle speed screw counterclockwise to
achieve exact 1500 RPM reading. The piston
valves should now be synchronized and the engine
should idle without holding any throttle pressure.

NOTE: If the engine has no ignition spark with

the throttle in the idle position but has proper
spark with the throttle lever slightly compressed,
the carburetor safety switches must be reposi-
tioned.

5. Test the throttle control lever by compressing and

releasing it several times. The lever must return to
the idle position quickly and completely.

Adjusting Carburetors

(TM-Style)

ADJUSTING CHOKE CABLES

1. Be sure ignition switch key is in the OFF position

and the brake lever lock is set.

2. Loosen the jam nut securing each choke cable

adjuster on the side of the carburetor.

! CAUTION

Do not force a pilot air screw when rotating it
clockwise; damage to the pilot air screw needle
tip will result.

! WARNING

DO NOT operate the snowmobile when any compo-
nent in the throttle system is damaged, frayed,
kinked, worn, or improperly adjusted. If the snow-
mobile is operated when the throttle system is not
functioning properly, personal injury could result.

! CAUTION

The air-intake silencer and boots must be in
position whenever the engine is run. If the
silencer is removed and the engine is run, a lean
condition will result. Therefore, DO NOT run the
engine when the air-intake silencer is removed.

4-24

0735-774

3. Slowly rotate one choke cable adjuster while

checking the choke lever for free-play. As soon as
all free-play has been removed from the end of the
choke lever, stop rotating the adjuster.

4. With free-play removed from the lever, slowly

rotate the adjuster again while checking the choke
lever for free-play. Adjust until 3 mm (1/8 in.)
free-play between front bottom edge of lever and
housing is attained. Securely tighten the jam nut.

0732-848

5. Repeat steps 3 and 4 on the other carburetor.

SYNCHRONIZING THROTTLE VALVES

NOTE: On F-chassis models, pry the air silencer

boot forward far enough to access the intake
bores; then proceed to step 4.

1. Open the air-intake silencer cover; then remove

the 3 Phillips-head screws securing the cover/tool
tray assembly to the silencer.

2. Tip the cover/tool tray assembly forward and out

of its slots and remove the assembly.

3. Using a large flat-blade screwdriver, remove the

resonator tabs from the air-intake silencer slots
and remove the resonator to access the intake
bores.

NOTE: The resonator can be removed more eas-

ily by removing the back tabs first.

4. With the throttle in the idle position, select a small

drill bit that will just fit under the cutaway of the
fixed throttle valve.

5. Using the same drill bit, check the clearance under

each adjustable throttle valve cutaway. If
clearance is different from the first carburetor
checked, adjust the throttle valve by loosening the
lever ring locking screw; then using an open-end
wrench, rotate each synchronizing nut in either
direction until the clearance is the same as the first
carburetor checked.

0734-445

6. After synchronization has been attained, hold the

synchronizing nut with the open-end wrench and
tighten the lever ring locking screw.

7. Install the resonator and cover/tool tray assembly.

NOTE: On F-chassis models, make sure the air

silencer boot is properly positioned over the car-
buretor bores.

ADJUSTING FUEL MIXTURE SCREWS

1. While counting the rotations, carefully rotate the

fuel mixture screws clockwise until lightly seated.

0735-774

! CAUTION

Do not force a fuel mixture screw when rotating it
clockwise; damage to the mixture screw taper
may result.

4-25

2. Rotate each fuel mixture screw counterclockwise

the same number of turns as noted in step 1 for an
initial setting.

ADJUSTING AIR SCREWS

1. While counting the rotations, carefully rotate the

air screws clockwise until lightly seated.

2. Rotate the air screws counterclockwise the exact

number of rotations ± 1/4 turn from the seated
position as an initial setting.

ADJUSTING ENGINE IDLE SPEED

NOTE: Make engine idle adjustment only after

the engine has reached running temperature.
Since the idle speed screw has not been adjusted,
apply slight throttle pressure to keep the engine
running. Allow engine to warm up for 2-3 minutes.

1. After the engine has been allowed to warm up for

2-3 minutes, fine-tune the idle speed screw until
the tachometer reads 1500 RPM.

2. Test the throttle control lever by compressing and

releasing it several times. The lever must return to
the idle position quickly and completely.

Throttle Cable

(VM-Style)

NOTE: Determine which type of cable is being

replaced and remove and install accordingly.

REMOVING

734-533A

736-742A

737-544A

1. Loosen the throttle cable adjuster jam nuts.

2. Remove the mixing body tops.

3. Remove the throttle cables from the piston valves.

4. Remove the throttle cables from the mixing body

tops.

5. Remove the handlebar pad and console.

6. Remove the cable ties securing the throttle cable.

7. Remove the throttle cable end from the throttle

lever.

8. Using Throttle Cable Removal Tool (p/n 1639-

963), push down on the throttle cable retaining
clip; then remove the cable from the throttle
switch assembly.

! CAUTION

Do not force an air screw when rotating it
clockwise; damage to the air screw will result.

! WARNING

KEY

1. Retaining Ring
2. Throttle Cable
3. Cable Tie
4. E-Ring
5. Washer
6. Nut

KEY

1. Retaining Clip
2. Throttle Cable
3. E-Ring
4. Washer
5. Cable Tie
6. Jam Nut

1
2

4
5

KEY

1. Cable Tie
2. Throttle Cable
3. Jam Nut
4. E-Ring
5. O-Ring
6. Retaining Clip

4-26

NOTE: On twin carburetor models, it may be nec-

essary to remove the PTO-side carburetor.

9. Remove the E-ring securing the oil-injection cable

to the control arm. Account for a washer.

10. Loosen the jam nut securing the adjustment cable;

then remove the cable from the oil-injection pump.

INSTALLING

1. Route the throttle cable from the throttle switch

assembly to the carburetors and oil-injection
pump; avoid any sharp bends or moving parts.

2. Install the oil-injection adjustment cable on the

oil-injection pump; secure with the jam nuts.

3. Install the oil-injection cable on the control arm;

secure with a washer and E-ring.

NOTE: Install the PTO-side carburetor if removed.

4. Install the throttle cable into the throttle switch

assembly making sure it snaps into place.

5. Install the throttle cable end on the throttle lever.

6. Secure the throttle cable to the steering post with

cable ties.

7. Install the handlebar pad and console.

8. Attach the throttle cable to each throttle valve. The

valve must seat in the groove of the throttle cable
end; then thread the throttle cable into each mixing
body top.

9. Install each piston valve and mixing body top on

the carburetor(s). Tighten securely.

10. Adjust the carburetor(s) (see appropriate

Adjusting Carburetors in this sub-section).

11. Synchronize the oil-injection pump (see Related

Items sub-section).

Throttle Cable

(TM-Style)

NOTE: Determine which type of cable is being

replaced and remove and install accordingly.

735-869A

737-754A

REMOVING

1. Loosen the throttle cable adjuster jam nut at the

bracket.

2. Remove the throttle cable from the pulley on the

throttle lever shaft.

3. Remove the handlebar pad and console.

4. Remove the throttle cable from the throttle lever.

5. Using Throttle Cable Removal Tool (p/n 1639-

963), push down on the throttle cable retaining
clip; then remove the cable from the throttle
switch assembly.

6. Open the belt guard; then remove the drive belt.

7. Remove the oil-injection cable from the control

arm.

NOTE: Some models are equipped with “control

rod” actuated oil pump. The control rod simply
snaps off and on at the control arm.

8. Loosen the jam nut securing the adjustment cable;

then remove the cable from the oil-injection pump.

INSTALLING

1. Install the oil-injection adjustment cable on the

oil-injection pump; secure with the jam nuts.

2. Install the oil-injection cable on the control arm.

! CAUTION

Compress the throttle control lever to ensure
free movement. If the throttle cable sticks or
binds, correct the problem before starting the
engine.

KEY

1. Retaining Clip
2. Throttle Cable
3. E-Ring
4. Washer
5. Cable Tie
6. Jam Nut

4
5

KEY

1. Cable Tie
2. Throttle Cable
3. Jam Nut
4. E-Ring
5. O-Ring
6. Retaining Clip

Content .. 45 46 47 48 ..